X-Git-Url: http://git.megacz.com/?p=sbp.git;a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2FTree.java;h=d2bfc4bbc46a6bf379bd79633fff7746bb1bc834;hp=7dbda47e2c258cf6749aecf81d2962aa157664f6;hb=d86c2344f6f5b958d56e2aa55e84af2dc76ab487;hpb=a4a48c32b18df6f5cc834d03fe0d5f864571380d

diff --git a/src/edu/berkeley/sbp/Tree.java b/src/edu/berkeley/sbp/Tree.java
index 7dbda47..d2bfc4b 100644
--- a/src/edu/berkeley/sbp/Tree.java
+++ b/src/edu/berkeley/sbp/Tree.java
@@ -17,16 +17,22 @@ public class Tree<T>
     private final Tree<T>[]    children;
     private final boolean      lift;
 
+    /** the element at the head of the tree */
     public T                 head()        { return head; }
 
     private Tree<T> lifted() { return children[children.length-1]; }
 
+    /** the number of children the tree has */
     public int               numChildren() {
         return lift
             ? (children.length-1)+lifted().numChildren()
             : children.length;
     }
+
+    /** the tree's children */
     public Iterable<Tree<T>> children()    { return this; }
+
+    /** the tree's children */
     public Iterator<Tree<T>> iterator()    {
         return lift
             ? new ConcatenateIterator(new ArrayIterator(children, 0, children.length-1),
@@ -34,24 +40,23 @@ public class Tree<T>
             : new ArrayIterator(children);
     }
 
+    /** get the <tt>i</t>th child */
     public Tree<T> child(int i)  {
         return lift && i >= children.length-1
             ? children[children.length-1].child(i-(children.length-1))
             : children[i];
     }
 
+    /** get the input region that this tree was parsed from */
     public Input.Region    getRegion() { return location; }
 
     public Tree(Input.Region loc, T head)                     { this(loc, head, null); }
     public Tree(Input.Region loc, T head, Tree<T>[] children) { this(loc, head, children, false); }
-    public Tree(Input.Region loc, T head, Tree<T>[] children, boolean lift) {
+    Tree(Input.Region loc, T head, Tree<T>[] children, boolean lift) {
         this.location = loc;
         this.head = head;
         this.lift = lift && children != null && children.length > 0;
-
-        Tree<T>[] children2 = children==null ? new Tree[0] : new Tree[children.length];
-        if (children != null) System.arraycopy(children, 0, children2, 0, children.length);
-        this.children = children2;
+        this.children = ArrayUtil.clone(children, Tree.class);
     }
 
 
@@ -86,6 +91,9 @@ public class Tree<T>
     public boolean isTransparent() { return false; }
     public boolean isHidden() { return false; }
 
+
+    // TreeFunctor /////////////////////////////////////////////////////////////////////////////
+
     public static interface TreeFunctor<T,R> extends Functor<Iterable<Tree<T>>, R> { }
     
 }